Liquid fuel burner and method of burner operation



Uct 15, 1935- H. 1 FlNLr-:Yl

LIQUID FUEL BURNERI AND METHOD OF BURNER OPERATION Filed June 25, 1954 2 Sheets-Sheet l Oct. 15, 1935. H. L. FINLEY 2,017,237

LIQUID FUEL BURNER AND METHOD OF' BURNER OPERATION Filed June 25, 1954 v 2 Sheets-Sheet 2 /72 venzor;

ym Jim.

Patented Oct. 15, 1935 UNITED STATES- PATENT OFFICEv LIQUID FUEL BURNER AND METHOD OF BURNER OPERATION Application June 25, 1934, Serial No. 732,232

and method of burner operation and has special v reference to liquid fuel burners for use in stoves, furnaces, water heaters and like heating appliances, the burner being adapted tov use liquid fuel commonly employed for such purposes in a new and efficient system of burner operation.

More particularly, this invention relates to a liquid fuel burner comprising` preferably a main burner section and a pilot section` in which the main burner section is either automatically controlled as to the rate'of flow of the liquid fuel and the intervals of burner operation in accordance with the temperature means external thereto, such as room temperature or water temperature, or is controlled by means of a manually operated valve. The main burner and pilot sections are preferably unitary in construction and comprise a channel-shaped ring preferably separated by parting walls or Webs into a plurality of individual compartments for receiving fuel conductors or wicks.

Heretofore, one of the most disadvantageous characteristics of liquid fuel burners was the exceedingly long period necessary for the establishment of burner operation when actuated either manually or by the temperature of the water or room which is to be heated. The burners are usually merely throttled to the rate at which fuel stantially lowered since just a sufcient quantity4 of liquid fuel is fed thereto for substantially immediate-vaporization. The normal rate of ow of the liquid fuel to the burner during the operative condition is controlled preferably by means of an adjustable metering valve and the normal rate of flow is accelerated just prior to ignition by a temperature-controlled valve which likewise controls the intervals of flow in accordance with temperature conditions.

In order to more fully understand the invention contemplated herein, the action of the two general types of. burners will be given. 'The range burnerv or vaporizing type of burner is constructed with operation. Means is provided to adjust this wick one or more annular channels of such width that when the fuel conductor or wick is in place in the annular channel, there is a wide space around the fuel conductor or wick so that the reflected heat can vaporize the oil in the bottom of the 5 channel. In burners of this type the wick is only used as a means of lighting the oil around the channel. Therefore, after lighting and until enough heat is generated to completely vaporize the oil, a dirty sooting flame results when used 10 under automatic control. When burners of this type are used under hand control, satisfactory operation is obtained due to the fact that the operator can regulate the supply of fuel in the channel according to the time required for gen- 15 erating. v Burners termed as the wick type are constructed with a single annular channel in which a close fitting wick is used with the lower end of the wick submerged in oil at all times during its 20 upwardly or downwardly to increase or decrease the flame surface of. the wick to regulate the rate of fuel used. In this type of burner, all of the fuel burned is vaporized off the top of the wick and due to the fact that the wick must be soft and 25 pliable for adjustment and to conduct oil upwardly a considerable distance, it is subject to charring and fusing, necessitating a trimming and cleaning every few days. 30

The burner shown and described in this application is constructed with an annular channel v into which a ceramic fuel conductor is fitted with little or no space between the side walls of the channel and the ceramic conductor. With this construction and the method used in distributing the fuel to the channel and the method used to control the fuel supply, the action is as follows:

When oil is admitted to the bottom of the channel either by thermostatic means or by hand, oil o its carried to the top of the ceramic fuel conductor by capillary attraction and lighted by the pilots; then the burner operates as a wick type burner by vaporizing the fuel on the top of the ceramic fuel conductor until sufficient heat is generated to 45 completely vaporize the fuel in the bottom of the channel. The burner then continues to operate as a vaporizing type `since the vapors rise up through the porous ceramic material.

. The apparatus to be hereinafter'more fully de- 5 -scribed provides a fully automatic control system for burner operation and consists essentially in a. thermostatic control operated by the temperature or a water heater for controlling the ow of liquid -fuel 'through a variable level fuel-chamber. The u 'f normal rate of liquid fuel ow from the constant level fuel storage chamber to the variable level fuel chamber is regulated by an adjustable regulating or metering valve. For maximum eiciency this rate of flow will be just suflicient for substantially immediatey vaporization in the burner. From the variable level fuel chamber separate fuel lines are directed to the main burner sections and the pilot sections. The pilot section operates constantly and is fed directly from the variable level storage chamber at a rate of flow which is predetermined. The main burner section, however, may be periodically shut off and a valve of anyl usual type is provided for periodically closing the fuel line to the main burner section at the direction preferably of a thermostaticallycontrolled element.

When the fuel line is cut off to the main burner section, the fuel level in the variable level fuel chamber will rise to a common level with that of the constant level fuel storage chamber, and thus, during an idle condition of the burner, the maximum height level in the variable level fuel chamber is controlled by the constant level liquid fuel storage chamber. Upon opening of the fuel line to the main burner section by the thermostatically-controlled valve or otherwise,the variable level fuel chamber may feed fuel therefrom at a rate materially in excess of the normal rate of flow from the constant level fuel storage chamber to the variable` level fuel storage chamber to prepare the burner .section for ignition. After the stored supply of liquid fuel in the variable level fuel storage chamber is dissipated, the normal rate of flow therethrough obtains which is just suncient for immediatefvaporization in the main burner section. v Y

One of the' objects of thisrinvention is to provide a liquid fuel burner of the type above referred to in which a predetermined supply of fuel may be fed to the vaporization chamber of the main burner section just prior to ignition at an accelerated rate of flow as compared to the normal rate of flow of liquid fuel during burner operation.

Another object of this invention is to provide a method of liquid fuel burner operation which consists in controlling the normal rate of flow of liquid fuel to the burner during an operative condition thereof and in accelerating the normal rate of ow just prior to ignition.

Other objects and advantages will hereinafter be more particularly pointed out and for a more complete understanding of the characteristic features of this invention, reference may now be had.

to the following description when taken together with the accompanying drawings, in which latter:

Figure 1 is a central vertical sectional view of the device of this invention as installed on a water heater;

Fig. 2 is an enlarged plan sectional view taken on the line 2 2 of Fig. 1, showing a fragmentary portion of the water heater;

Fig. 3 is a vertical sectionalview taken on the line 3-3 of Fig. 2;

Fig. 4 is a top plan view of the variable level fuel chamber with the top thereof removed;

Fig. 5 is a vertical sectional view taken, on the line 5 5 of Fig.f4; and Y Fig. 6 is a vertical sectionalview taken on the lineSB of Fig. 2.

Referring now more particularly to the drawings, the device of this inventioncomprises `a liquid fuel burner I preferably installed in a lower portion of a water storage tank II having the usual cold water inlet I2 and hot water outlet I3 communicating with a steel or copper preferably insulated inner tank I4. The water storage tank is of any usual type and the particular installation illustrated provides a central flue I through the inner tank I4 having a spiral deflector I6 which breaks up the hot flue gases and directs them'against the flue wall for efficiency in heat absorption.` A llame plate I 1 between the burner and ue acts as a baille for the flame and collects condensation of the flue.

The burner I0 is provided with an outer burner drum I8 and inner burner drums I9. and 20, the outer burner drum being spaced substantially from the inner wall of the lower portion of the storage tank. An air restrictor 2I is disposed at a point below the lower horizontal plane of the drums and occupies substantially the entire space between the vertical plane of the outer drum and the inner wall of the chamber to prevent excess air passing through the chamber and heater. The Water storage tank is preferably spaced from the floor and rests upon feet 22.

Referring now more particularly to Figs. 2 and 3 of the drawings, the burner I0 comprises a burner ring preferably in the form of an annular channel 23 of substantially U-shaped cross section which is subdivided by spaced Webs 24 and 25 into enlarged main burner sections 26 and 2'I and substantially smaller pilot sections 28 and 29, the main burner and pilot sections being of the same IU-shaped cross section. The upper ends of the vertically extending portions of the burner ring are provided with shoulders for supporting the innerdrums I9 and 20, the drums being annular and perforated over the surfaces thereof to provide for proper aeration and complete combustion of the vapors rising from the burner section. These drums I9 and 20 are preferably of chrome steel and form a combustion chamber for the hot gases between the spaced walls thereof. The outer drum I 8 is preferably formed of heavy steel with porcelain enamel finish and provides a draft to control the movement of the hot gases from the burner section.

In the drawings illustrating this invention, the burner ring is preferably formed of a sheet metal stamping, although it may be otherwise formed of cast material and the like. The pilot sections 28 and 29 communicate through openings 30 and 3|, respectively, with a conduit 32 preferably in the form of a pipe extending transversely in one direction of the burner ring, the pipe being preferably soldered or otherwise secured to the burner ring. The main burner sections 26 and 21 communicate through openings 33 and 34, respectively, witha conduit 35 extending in the other direction transversely of the burner section and beingformed preferably of a pipe soldered or otherwise secured to the lower end of the burner ring. Liquid fuel is directed to the pipe 32 and thence to the pilot sections through a conduit 36 communicating'with a variable level liquid fuel chamber 31. Liquid fuel is likewise directed from the chamber 31 through a conduit 38 connected to the conduit` 35 for Aconsumption by the main burner sections.V

The webs 24 and 25 are preferably disposed in the U-shaped channel in such a spaced relation as to formcomparatively small pilot sections and substantially large main burnersections. the

lwebs extending `upwardly a sufficient height to prevent the flow of liquid fuel from the main burner sections into the pilot sections by being higher than the initial fuel level in the burner sections and substantially lower than the height of the burner ring.

A plurality of wicks preferably of equal height are disposed in the main burner and pilot sections, the pilot wicks 39 snugly engaging the width of the channel and extending in one piece substantially the entire distance between the webs 24 and 25. The burner wicks 40 likewise snugly engage the width of the channel and are preferably formed in a plurality of separate pieces primarily for economy of replacement and to ll completely the transverse space between the webs 24-24 and 'Z5-25. 'Ihe wicks 39 and 48 are preferably of an` incombustible mineral material, such as ceramic material, this material being porous and assuring capillary attraction of liquid.

'Ihe variable level fuel chamber 31 comprises a simple housing preferably in the form of a hollow casting having an open-topped main body portion 4I with a cover 42 enclosing the open top. The housing has a well 43 formed by a depression in the bottom intermediate the ends thereof. A boss 44 depends from' the housing at the well portion 43 thereof and has a vertically extending aperture 45 communicating with the well 43, the vertically-extending aperture communicating also with a horizontally-extending aperture 46 which latter aperture extends from bore of the valve body 41 in axial alignment with the vertically extending bore 45. The end of the stem 50 is preferably tapered and is adapted to be seated at the end of the central aperture 48. The opposite end of the stem 50 is provided with a head l and has a compression spring 52 between the head and a shoulder formed by the reduced extension of the body portion 41, the spring tending to lift the valve stem from its seat.

The cover 42 has an apertured boss 53, the upper end of which is internally threaded to receive a sleeve 54 enclosing a rod 55 extending from a thermostatic regulating device 56. The thermostatic regulating device 56 is disposed adjacent the lower end of the water reservoir I4, an actuating element 51 of the thermostatic regulating device extending into the water of the storage tank to be governed in its operation by the temperature of the water to actuate the rod `55 longitudinally in either direction.

When the water in the storage tank I4 reaches a predetermined minimum temperature, the bimetallic element. 51 actuates the rod 55 in an upward direction. The lower end of the rod aouts against the head 5I in its positions of movement to limit the movement of the needle valve stem 50 so that the upward movement of the rod 55 permits the compression spring 52 to unseat the needle valve. In the operation of the burner, as will hereinafter be more particularly pointed out, when the water is heated to a desired temperature the bimetallic element actuates the rod 55 in a downward direction against the tension of the compression spring 52 to seat the needle valve. The valve stem 50 may obviously be closed manually if a thermostatic control is undesirable by merely substituting a conventional closure valve for the thermostatically operated rod 55.

An auxiliary well portion 43a formed by a depression in the well 43 is connected to the conduit 36 through a suitable connector 36a, and liquid fuel from the variable level liquid fuel chamber 31 is passed directly to the pilot lights. In order to insure a supply of liquid fuel at a constant rate to the pilot light and just suicient fuel for substantially immediate vaporization,

the connector 36a preferably comprises an enlarged polygonal head having reduced threaded connecting portions and an orifice therein of a predetermined size through which the liquid fuel must pass to the conduit 36. Liquid fuel is fed to the variable level liquid fuel chamber 31 from a constant level liquid fuel storage tank 58 through a nipple 59 threadedly engaging an aperture in the side of the housing 4I and a boss 60 extending from the side of an open topped housing 6| of the constant level liquid fuel storage chamber. The storage chamber 58 maintains a constant oil ow to the variable level fuel chamber at any desired rate of i'low.

Referring more particularly to Fig. 3 of the drawings, a manually operated metering valve 62 is shown in position in the constant level liquid fuel storage chamber, the valve having a comparatively steep threaded intermediate portion 63 for engaging internal threads of the aperture into which the stem is threaded for obtaining a vertical movement of the stem to vary the opening communicating between the chamber64 and the nipple 59 to thus predetermine the rate of ow from the storage chamber to the variable level fuel chamber 31. In order to accomplish this regulated flow', the lower end of the hollow cylindrical stem 65 of the metering valve 63 is slotted on one side thereof, the hollow portion of the stem extending at least between the horizontally extending portions 66 and 61.

Referring now more particularly to Fig. 6, the chamber 64 communicates with a source of liquid fuel through a needle valve structure comprising a body portion 68 having a central longitudinally extending aperture for receiving a stem 69 slidably therein, the lower end of the stem being reduced andjtapered to seat at the end of a bore in a reduced threaded extension of the body portion 68.' The bore 10 of the needle valve body portion communicates with a chamber 1I in which latter a screen 12 is positioned for straining the fuel of foreign substances entering the chamber from any source of supply through the inlet 13. When the needle valve 69 is open or in a raised position, liquid fuel from the chamber 1I passes upwardly through the bore 10 and through the horizontally-extending apertures 14 which the bore 10 intersects, and thence-into the chamber 64.

The longitudinal movement o-f the valve sm 69 is controlled by a iioat 15, the float being mounted on a pivotal arm 16, the free end 11 of which rests against the upper end of the stem 69. A safety float 11a disposed in a separate chamber 18 is mounted on one end of an arm 19, which latter is pivoted adjacent its other end on a pin 80. The free end of the arm 19 is provided with a hooked end portion 19a for supporting a weighted arm 8|, the arm being in position lto operate the needle valve stem 69 downwardly upon the operation of the safety float.

In operation the large iioat controls the liquid fuel level in the chamber 64. A partition separates this constant level chamber 64 from the smaller chamber 18 containing the safety float lla. The safety float 'lla is arranged to carry a spring loaded weight arm 8| and a slight in crease above the normal liquid fuel level permits the liquid fuel to iiow over a partition 82 into the emergency float chamber 18 raising the safety float and permitting the spring loaded arm' 8| to drop on the valve stem 69 and definitely cutoff the fuel flow. Depressing the lever 8| at the free end raises the Weight arm 8| and at the same time forces the small float downwardly replacing the chamber for further use.

The liquid fuel in the constant liquid fuel level storage chamber is permitted to flow at any predetermined constant rate to the variable level fuel chamber 31 through the metering valve 62, the latter being manually'adjustable to any desired rate of liquid fuel flow. When the needle valve 50 of the variable levelv fuel chamber is seated, the flow of liquid fuel from the constant level liquid fuel storage chamber to the variable ievel fuel chamber ceases after a common level has been attained therein. A store of liquid fuel is thus had in the variable level fuel chamber at a maximum height. After the water in the storage tank |4 reaches a predetermined minimum temperature, the bimetallic element 51 actuates the rod 55 in an upward direction to release the valve stem 50 and permit the spring tension thereof to unseat the needle valve. A substantial flow of stored liquid fuel is then had through the bores 48 and 46 into the conduits 38 and 35 and thence to the main burner sections.

The wicks of the main burner sections become saturated at a rapid rate by the above abnormal flow, the liquid fuel being admitted substantially centrally thereof and being directed by capillary attraction upwardly and laterally in opposite directions until nally the extreme outer and upper ends of the wicks adjacent to the continuously burning pilot sections are fed. The pilot lights thereafter ignite the fuel of the wick, and the flame, by reason of the entire wick assembly being saturated, will proceed immediately to spread over the entire burner and permit almost instantaneous complete ignition of the main burner sections.

In order to accomplish the above saturation of the wicks in a comparatively short time and to insure almost instantaneous spread of the ame over the entire burner, the needle valve of the variable level fuel chamber permits a substantial rate of flow therethrough greatly in excess of the rate of flow of the metering valve 62. Therefore, it may be said that the normal rate of ow of liquid fuel is materially accelerated just prior to ignition. By reason o-f the rate of flow through the needle valve of the variable level fuel chamber being greater than the flow of liquid fuel from the metering valve 62, the level of the chamber drops when the needle valve opens until the stored supply has substantially been depleted and thereafter the rate of flow through the variable level fuel chamber is the same asl that which 10 passes through the metering valve 62 to the burner which is just sufficient for substantially immediate vaporization in the burner. Initially, however, and just prior to ignition, the liquid fuel level in the burner, in the variable level l5 fuel chamber and in the constant level storage chamber is common to all. However, this initial liquid fuel level is vmaintained only temporarily, since after the burner sections are ignited, the fuel in the channel becomes vaporized and the 20 sections become hot enough to vaporize almost immediately the liquid fuel passing into the vaporization chamber thereof. Thus the liquid fuel level drops from a normal common level in all to aminimum level in the variable level fuel chamber 25 -and burner sections which is just sufficiently for substantially immediate vaporization.

While I have herein shown and described but one specific embodiment of the invention as applied to one specific type of burner apparatus, it 30 is to be understood that the details of construction may be varied within wide limits without departing from the spirit of the invention and that the invention s to be limited only within the terms of the appended claim. 35

-I claim:

In combination with a burner, a gravity fuel feeding system comprising a constant level chamber determining the maximum level to which the fuel may rise in the burner, a reservoir interme- 40 diate said chamber and burner, a conduit for connecting said reservoir and the burner that is capable of passing fuel at a rate materially exceeding the normal rate of fuel consumption of the burner, means controlling the flow of fuel 45 through said conduit, and means connecting said constant level chamber and reservoir operable to deliver fuel to said reservoir at a rate appro .imating the normal rate of fuel consumption of the burner whereby, upon the opening of said 5o fuel controlling means, the initial rate of fuel feed to and the level of the fuel in said burner materially exceeds that obtained during normal operation.

HAROLD L. FINLEY. 55 

